The present invention relates to shutter assemblies for electrical receptacles and electrical receptacles incorporating such shutter assemblies. Particular embodiments relate to shutter assemblies that may prevent access to electrical receptacles, such as but not limited to common household AC outlets.
Virtually every household in the industrialized world is equipped with sockets outlets or receptacles supplying electrical power. Electrical power is generally considered a necessity and, thus, virtually no modern home is ever designed without access to electrical power. Moreover, with the rapid increase in the number of electrical and electronic products in a typical home, power strips employing multiple power outlets have become commonplace, resulting in an increase in the number of electrical power outlets in the typical, modern home.
In addition, the increase in the number of electrical and electronic products in the typical home has increased not only the number of power outlets in the home, but also the number of electronic sockets and receptacles generally. Computers, stereo equipment, DVD players, television sets and the like are replete with plugs, pins, receptacles and sockets that must mate for effective operation of the equipment.
The natural curiosity of children can make the common household power outlet a dangerous device. Although children may not likely insert a standard three-prong plug of an electrical device into a wall outlet, it is not uncommon for a child to insert a single metal object, such as, for example, a key or a paper clip, into a wall outlet. Given the high voltage that typically exists in a common AC power outlet, such a scenario could be dangerous or even deadly. When children attempt to insert metal objects into computer or entertainment equipment receptacles, damage to the device may result.
Several attempts have been made in the prior art to preclude unwanted insertion of objects into power outlets. Some prior art devices employ a shutter plate that locks (Plurality of stop surfaces) when a single pin is inserted into the outlet. However, in these devices, the normal position of the shutter plate is in an unlocked position. Thus, by carefully inserting a pin into the outlet, or by just being lucky (or, more accurately, unlucky), the shutter plate may be subverted and the safety of the device compromised.
Other prior art devices have employed multiple shutters to prevent unwanted access to power outlets. However, in electrical sockets, the distance between the front surface of the socket to the electrical contact inside the socket is limited. Thus, multiple shutters must share this limited space, and performance may be compromised. In addition, because multiple shutters of some prior art devices have relatively large contact surfaces, relatively large amounts of friction is generated when the shutters slide as a result of plugs being inserted into the socket and against the contact surfaces. As a result, the contact surfaces and other surfaces can wear out quickly, especially when plugs with relatively sharp edges are inserted into the socket.